Sprinkle meat liberally with salt and pepper all over. Heat fat or oil in a heavy skillet and brown meat in on all sides.
Place veggies in a slow cooker. Place meat on top of veggies and pour broth and Worcestershire sauce over meat. Cover and cook on low for 8 hours or until meat is tender. Remove brisket and let rest for 10 minutes. Thinly slice against the grain. Sprinkle with parsley and serve with the vegetables and mashed or roasted potatoes.